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Assessment of Heavy metals concentration in holothurians, sediments and water samples from coastal areas of Pakistan (Northern Arabian Sea)

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Journal of Coastal Life Medicine 2017年第5期5卷 191-201页

作者： Quratulan Ahmed Qadeer Mohammad Ali Levent Bat The Marine Reference Collection and Resource Centre University of KarachiKarachi75270Pakistan Department of Hydrobiology Fisheries FacultySinop UniversityTR57000SinopTurkey

Objective: To determine Heavy metal concentrations in holothurians (Holothuria arenicola, Holothuria pardalis, Holothuria verrucosa, Holothuria atra, Ohshimella ehrenbergii, Holothuria cinerascens, Stolus buccalis and Holothuria leucospilota), sediments and sea water samples from both Buleji and Sunehri coasts bordering Northern Arabian Sea during January to December 2014 and to assess the level of bioaccumulation using bioaccumulation factors. Methods: Fe, Mn, Zn, Cu, Cd and Pb levels were determined by Perkin Elmer AAnalyst 700 Atomic Absorption Spectrophotometer. Biota concentration factor (BCF) and biota sediment accumulation factor (BSAF) were also calculated. Results: The mean concentrations of Heavy metals in body wall of sea cucumber ranged from 0.11 to 2.67, 0.43 to 8.93, 14 to 73, 0.76 to 7.12, 0.52 to 3.02 and 11 to 46 μg/g dry wright for Cd, Cu, Fe, Mn, Pb and Zn, respectively. The greatest biota-sediment bioaccumulation factor (BSAF) value for Zn (3.29) was observed in H. leucospilota at Buleji during pre-monsoon, indicating the species as microconcentrator. The BSAF values for Cd in sea cucumber ranged from 0.042 to 1.492. Conclusions: The results suggested that the studied sea cucumber species ranged from being microconcentrators to deconcentrators. The BSAF values of Cu, Fe, Mn and Pb were low, indicating the species as deconcentrators. Zn in all species from Sunehri coast is 'very bioaccumulative' (BCF > 5000) during all sampling periods. Cu, Fe, Mn and Pb can be considered 'bioaccumulative' (BCF < 5000).

关键词： Heavy metal Sea cucumber Karachi coast Northern Arabian Sea

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Heavy Metal Pollution Status and Health Risk Assessment in the Longjiang River

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Meteorological and Environmental Research 2017年第3期8卷 51-56页

作者： Lu Qiu Deng Qucheng Lu Wei Huang Yong Deng Chaobing Wang Xiaofei Wang Yunlong School of Chemistry & Chemical Engineering Guangxi University Environmental Monitoring Centre of Guangxi Zhuang Autonomous Region School of Geography Planning and Environmental Managementthe University of Queensland

[Objectives] The purpose of this research was to investigate the water quality of the Longjiang River in Guangxi. Concentrations of Heavy metals( As,Cd,Zn,Pb and Cu) in the surface water of Longjiang River were analyzed to figure out the distribution characteristics of Heavy metal pollutants in this area. [Methods]The Nemerow comprehensive index method and the health risk assessment model were adopted to evaluate the grade of Longjiang River water quality and the health risk level imposed by Heavy metals in the water. [Results] The concentrations of Heavy metals in each sampling point conformed to Grade-II water quality standard. The water samples collected on 13 sampling points of the Longjiang River were clean and not polluted by Heavy metals. The health risk values of Heavy metals As and Zn were greater than Cd,Pb and Cu in the Longjiang River,but still lower than the maximum acceptable risk level 5. 0 × 10^(-5)a^(-1). [Conclusions]Water quality condition reflected by the comprehensive pollution index and the health risk value of Heavy metal was consistent in the Longjiang River,showing as that the value in middle and lower reaches was slightly higher than in the upper reaches. As is the major pollutant of water environment health risk in the Longjiang River,and it should be regarded as the key object of water environment risk management in Longjiang River.

关键词： Longjiang River Heavy metals Nemerow comprehensive index method Health risk assessment

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Levels and Potential Ecological Risk Assessment of Heavy Metals in Sediments of Longjiang Wetland in Binzhou City

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Journal of Landscape Research 2019年第6期11卷 37-39,44页

作者： WANG Zihao ZHANG Zaiwang LI Luzhen MENG Xiangfang LI Xiaomeng College of Biological and Environmental Engineering Binzhou UniversityBinzhouShandong 256603China Shandong Engineering and Technology Research Center for Ecological Fragile Belt of Yellow River Delta Binzhou UniversityBinzhouShandong 256603China

Wetland is a unique habitat with great biodiversity and important ecological functions between land and water on the earth. With the irrational utilization of wetland resources, the ecological destruction and pollution of wetland are becoming more and more serious. To evaluate the pollution of Heavy metals in the sediments of Longjiang Wetland in Binzhou City, chromium(Cr), copper(Cu), zinc(Zn), cadmium(Cd) and lead(Pb) were measured by inductively coupled plasma mass spectrometry. Concentrations of Cr, Cu, Zn, Cd and Pb in the sediments were 5.3–13.6, 5.6–15.0, 16.6–33.0, 0.1–0.4 and 7.9–24.9 mg/kg dry weight, respectively. The concentrations of Heavy metals in Longjiang Wetland was lower than soil background values of Shandong Province and in lower level compared with those reported in sediments/soils of wetlands in some other locations. Based on geo-accumulation index(Igeo), Cr, Cu, Zn and Pb showed low levels of contamination at all stations, while Cd was observed at a moderate pollution degree. Potential ecological risk factor(E_r^i) and risk index(RI) values showed low ecological risk of Heavy metals in sediments of the wetland.

关键词： Heavy metal Longjiang Wetland Sediment Potential ecological risk assessment

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Spatiotemporal simulation and predication of Heavy metal(loid) concentrations in coal chemical industrial areas with a soil environmental capacity model

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International Journal of Coal Science & Technology 2018年第4期5卷 508-518页

作者： Kai Zhang Jiajun Yang Yuning Ji Yu Xia School of Chemistry and Environment China University of Mining and Technology (Beijing)Beijing 100083China

Heavy metal (loid)(HM) accumulation in the soil and the HM spatiotemporal distribution have important implication for soil pollution prevention and remediation. The present study investigated the concentrations and spatiotemporal distributions of lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr) and arsenic (As) in the topsoil of a coal chemical plant in Ningxia Aulonomous region (Ningxia), China. Topsoil samples (/?= 153) were obtained using the checkerboard method, and the HM concentrations were determined. The soil residual rates of the five HMs were measured with leaching experinients and were applied in a soil environmental capacity model to predict the quarHitiHive variation of the HM concentrations. The predicted results were employed to estimate the HM spatiotemporal distribution within 2() years with the Kriging technique. The number of sampling sites, where all five HM concentratio ns exceed their corresponding background values in Ningxia, would be increased from 0 to 90% within 1() years of the plant operation. In addition, Pb and Cd were distributed along the traffic routes. Mercury and As were distributed near fuel gas emission vents. Chromium was mainly accumulated in slag dumps. The study may provide the theoretical and practical foun d at ion for future HM pollution control in coal chemical plants.

关键词： Coal chemical plant Soil Heavy metal(loid) Kriging Simulation prediction

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Evaluation of Heavy Metals and Pesticide Residues in Dendrobium officinale Produced in Guangxi

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Medicinal Plant 2019年第5期10卷 73-76,81页

作者： Hua ZHU Ruiting HE Piaoling HUANG Wenqi YANG Anda WEI Yuanjing TAO Zhonghua DAI Guangxi University of Chinese Medicine Nanning 530001China Shandong DYNE Marine Biopharmaceutical Co. Ltd.Weihai 264300China

[Objectives]To establish a method for the determination of Heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five Heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five Heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five Heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of Heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.

关键词： Dendrobium officinale produced in Guangxi Culture substrate Heavy metal Pesticide residues

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Accumulation model and prediction of Miocene Heavy oil distribution in Gulf of Suez Basin,Egypt

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Global Geology 2018年第1期21卷 26-35页

作者： GUO Xufei SHAN Xuanlong DU Shang College of Earth Sciences Jilin University

The Gulf of Suez Basin is a very mature and extremely prospective petroleum province. Many Heavy oil fields have been found in the Basin,and such reserves are abundant. Characteristics and models of Heavy oil are analyzed in this study based on tectonic,basin evolution,stratigraphic distribution and geochemical data.The best reservoirs of Heavy oil are Miocene sandstone and limestone formations. Source rocks of hydrocarbon include deep limestone and shale of the Brown Limestone,the Thebes Formation and the Rudeis Formation.Thick evaporite rocks with rock salts and anhydrites deposited broadly throughout the basin are the most important regional seals,whereas Miocene shales are intraformational and regional seals that cover small areas. Heavy oil could be directly generated or densified during vertical migration along faults and reservoir accumulation.The Heavy oil accumulation model is a mixed model that includes three mechanisms: fault dispersal,sulfocompound reactions and hydrocarbons generated from immature source rock. After analyzing the model and the distribution of source rocks,reservoirs,Heavy oil fields and structures,it is concluded that the potential Heavy oil area is at the center of the basin.

关键词： accumulation model prediction Heavy oil distribution Gulf of Suez Basin

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Diagnostic Analysis on Heavy Rain Process of the Northeast-moving Southwest Vortex

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Meteorological and Environmental Research 2019年第3期10卷 1-10,17页

作者： Rao Xiaoqin Wang Shigong National Meteorological Center Beijing 100081China College of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

The moving path of southwest vortex and the mechanism of Heavy rain in the north were studied in order to find out the forecasting point of the northern Heavy rain,so as to improve the forecasting ability of the Heavy rain disastrous weather.A large-scale Heavy rain process in northern China from 18 to 21 July 2010 was diagnostically analyzed using meteorological conventional and intensified observation data and NCEP 1°× 1° reanalysis data.The result showed that the southwest vortex moved northeastward under the guidance of southwest airflow in the periphery of subtropical high,which was the direct influence system of the Heavy rainfall.The Heavy rainfall occurred on the east side of the symmetrical axis of the 700 hPa low vortex.The southwest jet provided abundant water vapor and potential instability energy for the occurrence of Heavy rainfall.The changes of vorticity advection and temperature advection in the lower and middle troposphere were the leading causes of affecting the development and movement of the low vortex.The low vortex moved along the positive vorticity advection increasing region and the warm advection increasing region.The dry and cold air intruded into the low vortex from the middle layer,which promoted the generation and development of the unstable stratification of upper cold and lower warm,and provided unstable and triggering conditions for Heavy rain.The water vapor transport from the Yellow Sea and the Bohai Sea was very abundant,and the water vapor flux was very high,reaching 30 g/(s·cm·hPa).It was the main reason for the maximum precipitation in Liaoning Province,which was the farthest from the southwest vortex source.The study deepened the understanding of the structural characteristics of the southwest vortex and revealed the dynamic mechanism of the northeast movement and development of the southwest vortex as well as the cause of rainstorm induced by interaction with other weather systems.It can provide some forecasting ideas and useful references for forecasting the movement of t

关键词： Southwest vortex Northeast-moving Heavy rain Vorticity advection Temperature advection

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Studies on Organic Matter and Heavy Metals in Soils around the Coal-fired Power Plant in Jinsha

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Meteorological and Environmental Research 2017年第6期8卷 56-62页

作者： Cao Rensheng Fan Mirigyi Huang Xianfei Yang Hao Zhang Zedong Hu Jiwei Qin Farixin Guizhou Provincial Key Laboratory of Information System of Mountainous Areas and Protection of Ecological Environment Guizhou Normal UniversityGuiyang 550001China College of Forestry Guizhou UniversityGuiyang 550025China Institute of South China Karst Guizhou Normal UniversityGuiyang 550001China

The concentrations of organic matter and Heavy metals( Hg,Cu,Pb,Zn,As and Cd) were analyzed in soils around the coal-fired power plant in Jinsha( Guizhou Province,China),and the ecological risks of these Heavy metals were evaluated by using the ecological risk warning assessment. The results showed that the concentration of organic matter in soils was high with the average value up to 41. 54 g/kg,which met the threshold limit for the concentration of organic matter at level 1. The concentration of organic matter in the study area was above the level of lack or the level of urgency. The results from the correlation analysis showed that there were correlations between organic matter and speciation of the Heavy metals( except Pb). The results from the ecological risk warning assessment showed that the order for the risk probability of individual ecological risk index above the level of no alarm was: Hg > Cu = Pb > Zn > As = Cd. The comprehensive indices revealed that the probability was 15. 62% for the sample locations at no alarm level,while the probabilities were 3. 13%,40. 63%,21. 87% and 18. 75% for sample locations at the levels of early warning,light warning,medium warning and serious warning,respectively. The results indicated that the ecological environment in this area has been adversely affected to some extent,and thus the treatment of Heavy metals pollution should be strengthened in the future.

关键词： Heavy metals Organic matter Effect Warning assessment

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α-decay Branching Ratios to Rotational Band of Heavy Even-even and Odd-A Nuclei

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原子核物理评论 2009年第S1期26卷 55-58页

作者： REN Zhong-zhou1,2,3,XU Chang2,3 (1 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000,China 2 Department of Physics,Nanjing University,Nanjing 210008,China 3 Joint Center for Particle,Nuclear Physics and Cosmology,Nanjing 210008,China) Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China Department of Physics Nanjing UniversityNanjing 210008China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210008China Department of Physics Nanjing UniversityNanjing 210008China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210008China

By using a simple barrier penetration approach,we predict the α-decay branching ratios to members of ground-state rotational band of Heavy even-even No isotopes. We also extend our approach to calculate the α-decay branching ratios to the rotational band of Heavy odd-A nuclei. The theoretical branching ratios of α-decays are found in good agreement with the available experimental data.

关键词： α-decay branching ratio Heavy nuclei

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Electromagnetic field effects on nucleon transverse momentum for Heavy ion collisions around 100 A MeV

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Nuclear Science and Techniques 2017年第12期28卷 255-261页

作者： Xian-Gai Deng Yu-Gang Ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China ShanghaiTech University Shanghai 200031China

With taking electromagnetic field into account for the transport model of Boltzmann-Uehling-Uhlenbeck,electromagnetic effects are studied for ^(208)Pb +^(208)Pb collisions around 100A MeV. Electromagnetic field evolution during the collisions was estimated. It was found that the electric field has an obvious effect on the transverse momentum(p_T) spectra of nucleons during Heavy ion collisions, and leads to different minimum position for the peak of p_T spectra of nucleons versus beam energy when the electric field is switched on. For the magnetic field, it affects the z-axis direction distributions of nucleons for central Heavy ion collisions at lower energy.

关键词： Heavy ion collision Electromagnetic field Transverse momentum

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